Electrical phase shifting device



Jan. v2O, 1942. A, KAHN ELECTRIGALPHASE SHIFTING DEVICE 2 sheets-shut .1-

Filed Nov. l, 1958 INVENTOR nl. mfp #ff/v ATTORNEY n Jan. 2o, 1942.

A. KAHN Filed Nov. l, 1958 ELECTRICAL PHASE SHIFTING DEVICE 2 Sheets-Sheet 2` INVENTOR QL Hei nH/v ATTORNEY Patented-Jan. 1942 j i Y A amano;

ELECTRICAL musaslsnlrrln'dv nevica i Alfred Kahn, Ozone Park, N. Y., assignor to Radio4 Corporation of America, a' corporation of Dela- Application November 1,1938, serial No. 238.167

Claims. '(Cl. 1787-53) This invention relates to phase delay devices Other objects of the invention will appear in and is useful in multiplex telegraph systems, both -7 the following description, reference being had to wire and radio, and particularly so in such systhe drawings in which: I

tems where signals from one -station are relayed Figure 1 is an illustration'of a multiplex radio through a-second station to a third station. This system employing the phase shifting unit.

relaying voi? messages is customarily referred to VFigure 2 illustrates a modiiied form voi! phase I as channel extension. In time division multiplex shifter. A 4 telegraph systems the metallic conductor or radio To illustrate ycompletely every, part of a multilink is assigned to the' terminal equipment, conplex system from the receiver to the transmitter sisting of senders or receivers,vas the case may 10 WOU-ld render this description unbeal'bly 1011;

' be, for equal portions of time by' a distributing therefore. well known parts and units` in such a means and the commutator or distributor at the system have been shown in symbolic .or in par- 'receiving `end must run in synchronism and tial diagrammatic form.

phase with a corresponding commutator or disi Let it be assumed lthat a.` branch station at `tributor at the transmitting end. `15 Chicagodesires to transmit to say, San Fran-` l Each channel is l,assigned to the circuit for an cisco, by having the communication relayed equal period of time, this period being deterthrough another station, say, one located in New mined by the design of the `distributingmeans A VYork city. Such relaying Vof communication is and the speed of operation ot the system. It has not only preferable from an economical standbeen found preferable, though not essential, to point in most cases, but at certain times it is imassign the'circuit to a channel at approximately possible to send direct communication between the middle oi. a signal unit in order to permit the two stations because of atmospheric conditions signal unit to reach itsgsteady state value, for or for otherreasons,.while the transmission over consistently good operations. the indirect route is unaffected.

The dot of the Morse code is adopted as the The drawingsV illustrate only the apparatus basic signal unit usually called a baudf For used at the main, or relaying, station as the inmore 'detailed explanation of a multiplex system vention can be fully understood without illusreference is made to a patent of R. E. lMathes, trating the apparatus at the other stations. No.1,979,484, November 6, 1934.- v The two triodes A and B which may be incor- 11' multiplex signaling, vparticularly with refer- 30 porated in one evacuated enclosure I, have inence to transmitting, the clutch mechanism of directly heated cathodes 2 and ,3, though the trithe automatic tape transmitter head can be readodes may be entirely separate and may have diily adjusted to retard the phase ofthe signal' rectly heated cathodes. The grid l of triode A units so that the distributor assignment of each is connected through resistance 5 to the plate E channel to the circuit occurs at the center of a 35 of triode B, while the grid 'l of the latter triode baud. However, where signals from a distant is connected through resistance 8 to the plate 9 station are received byV meansl of a multiplex reof the former.. The grid 6 is also connected ceiving apparatus and are combined with local throughresistance I0 and conductor il to posignals and transmitted to another station, metentiometer I2 which is connected across battery chanical means cannot be advantageously uti- 40 I3 or other suitable source of direct current/A `lized to phase the signals ofthe extended chant The grid 1 is similarly conducted through renel with the localdistributor and it is, therefore, sistance I4 to potentiometer I2. lll'his potentipreferable to employ electrical phase Shifters or ometer permits one to adjust the bias on the delayers forthe relayed signals. grids. The plate 9 is connected through resist- .One of the objects of my invention is to proances I5, I6 and Il, to the other plate E. An vide an electrical phase shifter for signal transadjustable tap I8 connects the positive side. of mission. battery I9 to resistance I6 so that plate potential Another objectl is to provide an electrical phase is applied to the triodes. VThe circuit thus far I shifting device that can be inserted without com described is similar to the locking arrangement plications directly into. a multiplex system al- 50 disclosed in my Patent No. 1,995,181, Marchv 19,

-readyin operation. 1 1935.

operation and thatvneeds no attention after once Another object of my invention is to provide an The output resistances I5 and Il are connected electrical phase shifting device that is stable inv to grids 20 and 2I-,'respective1y, of gas tubes C` and D, commonly referred to as thyratrons` or 5 grid glow tubes, which have the property of being adjusted for producing a given phase delay.

battery unit |3. ed by conductor 53 and switch 5| with the ccnstarting the plate current but being independent of suchgrid while the platecurrent is ilowing. The plate 22 of the gas tube C is'connected to one end of relay coil 23; the other end of thisl coil is connected to plate 24 of the other gas tube D. The center tap 25 of the relay coil 23 is connected by conductor 26 to the positive side of battery 21.

Batteries I3, 21 and I9 are connected in series and constitute one bank of batteries as indicated u by the polarities given on the drawings.

The grid 2l is connected to one end of re-` sistance I6 through resistance 28 and the grid j2| is connected to the other end of resistance |6 through resistance 29. Grid 2|| is connected to the grid 2| by resistancesll and 3| andthe center point of these two resistances is adjustably connected to resistance 33 which, in parallel with resistance 34, is connected between ground and the negative side of the battery AI3. Resistances 28, 30, 3| and 29 act as a voltage divider arrangement to permit one to adjust the voltages applied to the grids of the gas tubes.

A condenser 31 is connected between grid 20 and conductor 38, which is adjustabiy connected to resistance 34. Resistance 39 and adjustable resistance 49 are connected in shunt to condenser 31. Grid 2| is likewise connected by condenser 4| to the conductor 38 and this condenser is shunted byV resistance 4,2. and adjustable resistance 43. The adjusting devices are connected together at 43' so that simultaneous adjust- I ment is provided.

Condensers 44, 45 and 46 are adapted to be connected across the plates 22 and 24 of the gas tubes C and D. These commutating condensers, as they are usually called, alternately interrupt the plate current of the lgas tubes when they are once ired by the potential appearing alternately on the grids 29, and 2|, and the grids thereupon resume control.

When the upper portion of coil 23 is energized, relay tongue 41 is moved upwards into engagement with the contact 46 which is connected to the positive terminal of battery 21. When the lower portion of coil 23 is energized, tongue 41 Cil Y 2,270,449 being dependent upon the grid potential for city for relaying through the transmitter of the latter to the San Francisco station. It will also be assumed that channels I and II of the New York transmitting distributorv 55 are being used for direct communication between the New York station andthe San Francisco station, and that channel III of the distributor 55 is being used for extending the Chicago communication to San Francisco. Of course the various channels could be assigned in any order desired and the above description is given only for the understanding of the operation of my invention.

The signal coming in from the Chicago station will reach the receiving antenna 56 after which `it will be ampliied, detected and further amplied and then tone keyed, as particularly explained in patent to Beverage and Peterson, No. 1,874,866, August 30, 1932. I The signals are then transmitted over lines 58, whichmay or may not be of Aconsiderable length, and at the local station the signals are rectified and further ampliiled as symbolically indicated at 59. The signals are next conveyed to a coupling tube stage also symbolically illustrated at 60, which feeds the composite signal into the receivingA distributor 6| at the New York station. The distributor 6| transfers the signals to the channels I, II and III. The signals of I and 1I are transferred to locking circuits and utilization devices not shown. Y u

The .signals of the extendedA channel II are fed into locking unit 62 which produces alternating potentials across the conductors 63, 64, that mark the beginning and ending of the Morse code or other signals. The manner in which the rectifler coupling tube, distributor and locking unit operate are fully explained in my Patent No. 1,995,181, dated March 19, 1935, and it would unnecessarily lengthen" this description to repeat theory of operation here.

When these signals arrive from Chicago over channel III, they will, except in rare instances, be out of phase with the signals arriving at the transmitter distributor '55 `from local transmitis drawn into engagement with contact 49 which is connected to the negative terminal of the battery assembly, that is, the negative terminal of 'I'he relay tongue 41 is connectshift device, the operation will be explained in connection with the relaying of signals from some distant station, say, Chicago, whose apparatus is not shown, to another station, say, San Francisco, whose apparatus also is not shown.

Let it be assumed that at Chicago station, channels I and II are being used for direct communication with the station at New York city and that channel III at Chicago is being used for communicating with the station at New York ting channels I and II; consequently, if the distributor arm 65 of the transmitter picks the signals from channels I and II at the center of the baud it Will not pick the signals from extended channel III at such center. My invention provides an electrical adjustment between the locking unit 62 and the transmitting distributor 55 that will permit one to electrically delay the phase so that the signals from channel III can likewise'be picked off at the center of the baud.

As has been previously said, positive and negative potentials appear alternately across conductors 63 and 64. By this is meant that the potentials are positive and negative in respect Yto each other without reference to ground potenti-al.l

Let it be supposed that for the moment conductor 63 is positive and 64 negative. The positive charge on conductorv 63 sends charging current through condenser 66, resistance l0, and conductor Il, lto the negative side of the battery. 'I'his makes the grid 4 positive, or less negative, in respect to the cathode 2 connected to the positive end of potentiometer I2. The negative charge of conductor 64 chargescondenser 61 in a reverse direction and sends current through resistance I4 to make the grid 1 negative in respect to its cathode. This causes current to flow from positive conductor i8 through resistance I6 and the plate 9 of the tricde to the cath- 0de 2 and blocks the current flow through plate 3 to cathode 3 if this state of'aiairs has not already-previously been reached. This action is the well known locking action taking place in the locking unit'as referred to in myabove mentionedpatent. Y

The current iiowing through resistance 'I5 the lack of current in plate lresistance |1 causes the tube 2| of the Iother gas tube to grow more strongly positive. vThe grid 20, therefore, does I not rire gas tube C but the positive potential on grid 2| does cause gastube D to fire and plate current ows from conductor 28 to the lower part of coil- 23 to plate 24, cathode 33, back to the negative terminal of battery 21, This draws i 3 ring ofthe tubes 2| and.22 can also be adjusted by varying the grid bias by means of potentiometer 33, as these adjustments Vdelay the makes grid 20 of the gas tube less positive and phase oi the signals by delaying the firing of the tubes. 'Ihe signals can also be delayed by ad- Justing the commutating time of the tubes by means of the plate condensers 44, 45 and 46. In Fig. 2 I have shown in the grid connectionen. inductance 1| shunted by resistancey 12 .and two resistances 13 and 14 connected from grids 20 and 2|, respectively, to the grid bias con-- ductor as. mso, in this gure I have shown a resistance 15 connected across the plates 22 and '24 with the positive voltage terminal connected polarized relay tongue 41 into engagement with contact 49 and anegative pulse appears on dis- Y tributo'r contact 52.

yThe ow of platecurrent through gas tube,

D charges condenser 45 `so that its terminal 69 is positive with respect to its terminal 1|l. This polarity is produced by the absence of current .to the center of the resistance.

Resistances 16 and 11 are connectedbetween the plates and a relay coil 18, for operating therelay tongue 4.1.

Parts inthis gurethat are similar to those in Fig. 1 have the same reference characters.

In-Fig. 2 the time of ring, and the delay oi the signal phase, can be adjusted by adjustment of resistances in a way 'that will be readily underin the upper part of coil 23 and the presence of *u current in the lower part of the coil. It will thus be seen that full battery Apositive potential is applied tothe terminal 69, whereas a lesser positive potential, namely, thev potential from plate to cathode of tube D is applied to ttheterminal 1U.

When the Alocking unit 62 reverses the potential of the signal, conductor 63 becomes negative and conductor St' positive in Arespect to each other. The -two condensers 66 andA6`1 then discharge lin series through resistances |4 and It), the cirtor arm. When so used it makes it unnecessary to cuit being completed through the locking unit '32. ,This makes the grid H negative and grid v'l positive. Plate current then stops flowing through resistance I5 to plate 9 and commences to flow through resistance |1 to plate 6. This places maximum positive potential on the gri-d 20 .and a reduced positive .potential on the grid 2| due tothe absence of drop in the upper part of resistance I6 and the existence of a drop in the lower partv voi' such resistance. This causes vacuum tube C to nre and plate current passes through the upper part of coil 23 and plate 22.` This draws the relay tongue 41 into engagement 'with contact 48 and a positive potential is applied to contact 52. y i When the tube C commences to draw current the voltage on condenser lead 69 immediately drops to the plate-cathode :voltage of tube C.

stood without further explanation.

While my invention has been disclosed in connection with channel extension systems, it is useful alsorin the phasing of local signals to be assigned to the transmitter through the distribumake mechanical adjustment for this purpose.

By referring to my hereinbei'ore mentioned patent it will be seen that the tube stages A and way in the drawings.`

It will be apparent that one can determin when the correct phase adjustment is obtained by utilizing well known indicators such as the stroboscope shown in the application of VR. E.

`Mathes, led Nov. l, 1938, Ser; No. 238,168.

Having described my invention, what 4I claim 1. In a multiplex telegraph system, .a transmitter. a message channel, a gas triode adapted Condenser 45 cannot discharge immediately and Y for" an appreciableglength df time its negative terminal 10 makes plate 24negative with respect to its cathode. The current flow through gas tube D immediately stops and the grid 2| resumes control, but since suiliciently a negative or insufficiently positive potential is applied to grid 2| at this time to prevent the ring -of thev tube,

` no current ows. The gas tubes are thus setfor another reversal of current from locking unit 82 and the pulses areconveyed to the transmitting distributor 55.

wIn order todelay the phase of the signals in 4 channel III so that thevcenter of the baud o! this channels signals occur at the same time as the centers of the 4bauds of channels I and II, I adjust the contacts of resistances 4o and 43 shunting the condenser-s 31 and 4|. This regulates the drop in resistances 23 or 29, and delays.

the time of building up of the voltages on grids 20 and 2| to the firing point so that the. signals occurring ir'r'tfieV relay coil 23 can be delayed due to the delay ofthe tiring of the gasl tubes. The

between the. plate and cathode of the triode for applying potentials to the transmitter, a conto be fired by a'predetermined charge on its grid. means for connecting said channel `to the grid and cathode of the triode, means connected between the plate and illament'of the triode for applying potentials to the transmitter, a reactance connected between the grid and cathode of the triode..means to adiustably by-pass cury rent around. the reactance to delay the building up of signal potentials'on the grid to the ring point of the triode, and means to extinguish the plate current after decrease of grid potential below the firing point. i

2. In a multiplex telegraph sysem,4 a transmitter, a message channel, a gas triode adapted to be ilred by a predetermined charge on its Vgrld,`mean`s for connecting said channel to the` grid and cathode of the triode, means connected denser connected between the grid and the cathode of the triode, means'to adjustably by-pass current around the condenser to delay the `building up of signal potentials on the grid to the ring point of the triode and means to extinguish the plate current inthe tube after it has been I fired by its grid.

3. In a multiplex telegraph system, a trans-` mitter, a message channel, a pair of gas triodes, adapted to be fired by ar predetermined charge on their grids, means for connecting said channels to the grids and cathodes of said triodes, means connected to the plates of the,y triodes for applying potentials to said transmitter, a condenser l.

connected between said plates for commutating the plate currents and means to variably delay the building upof signal potentials on thegrids to the tiring point of said'triodes. l 4

.4. In a multiplex telegraph system, a .transmitter, a message channel, a pair of gas triodes,

adapted to be fired by a predetermined charge on their grids, means for connecting said channel to the grids and cathodes of said triodes,

means connected to the plates of the triodes for applying potentials tosaid transmitter, condensers bridged between the grids and cathodes of said triodes, an adjustable shunt around each of said condensers to delay the building up of signal potentials on said grids tothe firing point of said triodes and a condenser bridged across the plates to commute the plate current alternately fromy one plate circuit to the other.

5. In a multiplex channel extension system, a transmitter, a plurality of transmitter messagechannels, means to connect said channels in succession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect Asaid receiver message-channels in successionv to channels, and-its anode and cathode to one of said transmitter message-channels, means operated by a signal pulse. in the last mentioned receiver message-channel for building upa' charge on' said grid, means for 'varying the time of the building up of the charge on said condenser to cause the triode to strike when the last mentioned ,transmitter message-channel is connected to said transmitter, and means for rendering the anode A said receiver, a gas triode, means to connect the said receiver, a gas triode, means to connect the grid and cathode of said triode to one of said 'receiver message-channels, means to connect its anode and cathode to one of'said transmitter message-channels, means operated by a signal pulse in the last mentioned receiver message- `channel for building up a charge on said grid to cause the triode to strike, means to quench 'said triode after termination of said signal pulse and means to vary the time of the building up of the charge. on said grid -for synchronizing the signal pulse with the connection of the last-mentioned transmitter message channel to said transmitter.

, 6. In a multiplex channel extension system, a

transmitter, a plurality of transmitter messagechannels, means to connect said channels in succession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect said receiver message-channels in succession to said receiver, a gas triode, means to connect the grid and cathode of said triode to one of said lreceiver message-channels, and its anode and cathode to one of said transmitter message-channels, means operated by a signal pulse in the last 'mentioned receiver message-channel for building up a charge on said grid, means for varying the time of the building up of the charge on said condenser to cause the triode to strike when the last mentioned transmitter message-channel is connected to said transmitter, andmeans for rendering the anode of said triodenegative in o de of said triode to one of said receiver messagei grid and cathode f said tn'ode to one of said receiver message-channels, and its anode and cathode to one of said transmitter messagechannels, a condenser connected between the grid and cathode of the triode, means to delay the building up of a charge on said grid by a signal pulse inthe last mentioned receiver messagechannel, means to quench said triode after termination of said signal pulse in the last mn-v tioned receiver message-channel, and means to vary the time of building up of the striking charge on said condenser'to cause the tube to str ike when the last mentioned transmitter message-channel is connected to said transmitter.

9. In a multiplex channel extension system. a

transmitter, a plurality of transmitter message- Y channels, means to connect said channels in succession to said transmitter, a. receiver, a plurality of receiver message-channels, means to connect said receiver message channels in succession to said receiver, 'a gas triode, means to connect the grid and cathode of said triode to one of said receiver message-channels, and its anode and cathode to one of said transmitter messagechannels, means operated by signal marks in the last mentioned receiver message-channel for causing the triodeto strike when the last mentioned transmitter channel is connected to the transmitter and` means operated by signal spaces to quench said triode.

10. In a multiplex channel extension system, a

transmitter, a plurality of transmitter messagechannels, means to connect saidV channels inzsuccession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect said receiver message-channel in succession to said receiver, aresistance, a gas triode, means to connect the grid of said triode to'one of said receiver message-channels through said resistance and its anode to one of said transmitter message-channels, a condenser connected between the grid and cathode of the triode, means to delay the buildingup of a charge on said grid by a signal pulse in the last mentioned receiver message channel, a variable resistance connected around said condenser for varying the delay to cause the triode to strike when the last mentioned transmitter message-channel is connected to said transmitter, and means to quench said triode after termination of said signal pulse in the last mentioned receiver message-channel.

11. In a multiplex channel extension system, a transmitter, a plurality of transmitter messagechannels, means to connect said channels in succession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect 2,.32'0,4=4,9Y` said receiver message-channels in succession to said receiver, a gas triode, a resistance, a source o! negative grid bias, means to connect the grid of said triode to one side of said receiver messagechannels through said resistance and the cathode to the other side thereof through said source of negative bias, means to connect one of said transmitter message-channels across the anode and cathode of said triode, a condenser connected between the grid and cathode of the triode, a resistance around said condenser, and means to vary the second mentioned resistance to cause the triode to strike when the last mentioned transmitter message-channel is connected to said transmitter. i

12. In a multiplex channel extension system, a transmitter, a plurality of transmitter messagechannels, means to connect said channels in successlonto said transmitter, a receiver, a plurality of receiver message-channels, means to connect said receiver message-channels in succession to said receiver, a gas triode, a resistance, a source of negative grid bias, means to connect the grid of said triode to one side of said receiver messagechannels through said resistance and the cathode to the other side thereof through said source of negative bias, means to connect one of said transmitter message-.channelsyacross the anode Vand cathode of said triode, a condenser connected between the grid and cathode of the triode. a resistance around said condenser, and means to vvary the second mentioned resistance to cause `the triode to strike when the last mentioned transmitter message-channel is connected to said transmitter and means to quench said triode after termination of said signal pulse in the last mentioned receiver message-channel.

13. In a multiplex channel extension system, a

transmitter, a plurality of transmitter messagechannels, means to connect said channels in succession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect said receiver message-.channel in succession to said receiver, a pair of resistances, a rst and second gas triode having their inputs connected in opposition to one of said receiver message channels through said resistances and their anodes in opposition to one of said transmitter mes'- condenser.

sage-channels, a condenser connected between the grid and cathode of each triode, means to delay the building up of a charge on said grid by a signal pulse in the last mentioned receiver message channel, a variable resistance connected around said condenser for lvarying the charging time of the condenser to cause Athe triode to strike when the last mentioned transmitter message channel is connected to said transmitter, and means to quench one triode when the other one strikes.

14. In a multiplex channel extension system, a transmitter, a plurality of transmitter messagechannels, means to connect said channels in succession to said transmitter, a receiver, a plurality of receiver message-channels, means to connect said receiver message channel in succession to said receiver, a pair of resistances, a, first and message channel, and a variable resistance connected around said condenser for varying .the charging time of the condenser to cause the triode to strike when the last mentionedv transmitter message, channel is connected to, said transmitter.

15. In a: telegraph system, a communication link, a message channel, a gas triode adapted to be iired by a predetermined charge on its grid, a resistance connecting the grid of said triode to said channel, means connected between the plate and filament of the triode for applying potentials to the communication link, a condenser connected between the grid and cathode of the triode, means to adjustably by-pass current around said condenser to vary the drop in said resistance f or varying the time required to build up a tiring potential on the condenser, and means to extinguish the plate current of the triode after it has been red by its potential on said ALFRED KHN. 

